Volume 537 Issue 7622



Alternative career paths should be celebrated, not seen as a compromise.

doi: 10.1038/537585a


We need to know what the 1.5 °C warming target will involve — even if we don’t reach it.

doi: 10.1038/537585b


United Nations conference on cities needs to set goals for the next 20 years.

doi: 10.1038/537586a



Construction of the Five-hundred-meter Aperture Spherical Radio Telescope (FAST) is complete, but debugging has only just begun.

doi: 10.1038/537593a


Chan Zuckerberg Initiative aims to have major impact by 2100.

doi: 10.1038/nature.2016.20649


Genetic analyses of endangered animals reveal high level of interbreeding with hardier American species.

doi: 10.1038/537596a


Worries include how to coordinate research programmes and resources from different countries.

doi: 10.1038/nature.2016.20658


Former Soviet nation bids for independence from Russian fossil fuels.

doi: 10.1038/537598a


Research struggles in a country in economic free-fall.

doi: 10.1038/nature.2016.20670

News Features


Tensions between Cuba and the United States are easing. But researchers still struggle to join the scientific world.

doi: 10.1038/537600a

News & Views


Crossing different plant varieties to improve yield and fertility is common practice. A dissection of the genomic architecture that underlies such hybrid vigour might help to inform future crop-improvement strategies. See Article p.629

doi: 10.1038/nature19433


A technique that combines magnetic resonance with nuclear medicine has been used to image the distribution of a radioactive tracer, potentially opening up a powerful and innovative approach to medical imaging. See Letter p.652

doi: 10.1038/537621a


An unexpected function has been assigned to part of the molecular machinery that synthesizes the bacterial cell wall — a dramatic shift in our understanding that may have major implications for antibiotic development. See Article p.634

doi: 10.1038/537622a


Interventions to improve crop yields in rural China through collaboration between researchers and farmers illustrate how the goal of increasing global food production can be approached locally. See Letter p.671

doi: 10.1038/nature19431


Carbon emissions from the Arctic tundra could increase drastically as global warming thaws permafrost. Clues now obtained about the long-term effects of such thawing on carbon dioxide emissions highlight the need for more data.

doi: 10.1038/537625a


Disturbances in internal water equilibrium can be debilitating for mammals. Two studies pinpoint areas of the mouse brain that respond to and anticipate thirst, preserving systematic fluid regulation. See Letters p.680 & p.685

doi: 10.1038/537626a


The emergence of complex, dynamic molecular behaviour might have had a role in the origin of life. Such behaviour has now been seen in a reaction network involving small, organic, self-replicating molecules of biological relevance. See Letter p.656

doi: 10.1038/537627a



Insights into the genomic architecture of heterosis for grain yield in rice are presented, and further mapping of grain yield loci resolves candidate genes that could be useful for breeding.

doi: 10.1038/nature19760


SEDS proteins are core peptidoglycan polymerases involved in bacterial cell wall elongation and division.

doi: 10.1038/nature19331


Respirasomes are supercomplexes of mitochondrial electron transport chain complexes that are responsible for cellular respiration and energy production; a cryo-electron microscopy structural study of the respirasome is presented.

doi: 10.1038/nature19359


Respirasomes are supercomplexes of mitochondrial electron transport chain complexes that are responsible for cellular respiration and energy production; cryo-electron microscopy structures of mammalian (sheep) respirasomes are presented.

doi: 10.1038/nature19774



Long-term pre- and post-eruption observations of the classical nova V1213 Centauri reveal that its progenitor was a dwarf nova and that the mass-transfer rate increased considerably as a result of the nova explosion.

doi: 10.1038/nature19066


Magnetic resonance imaging (MRI) provides fine spatial resolution, spectral sensitivity and a rich variety of contrast mechanisms for diagnostic medical applications. Nuclear imaging using γ-ray cameras offers the benefits of using small quantities of radioactive tracers that seek specific targets of interest within the body. Here we describe an imaging and spectroscopic modality that combines favourable aspects of both approaches. Spatial information is encoded into the spin orientations of tiny amounts of a polarized radioactive tracer using pulses of both radio-frequency electromagnetic radiation and magnetic-field gradients, as in MRI. However, rather than detecting weak radio-frequency signals, imaging information is obtained through the detection of γ-rays. A single γ-ray detector can be used to acquire an image; no γ-ray camera is needed. We demonstrate the feasibility of our technique by producing images and spectra from a glass cell containing only about 4 × 1013 atoms (about 1 millicurie) of the metastable isomer 131mXe that were polarized using the laser technique of spin-exchange optical pumping. If the cell had instead been filled with water and imaged using conventional MRI, then it would have contained more than 1024 water molecules. The high sensitivity of our modality expands the breadth of applications of magnetic resonance, and could lead to a new class of radioactive tracers.

doi: 10.1038/nature19775


A few-component network of biologically relevant, organic reactions displays bistability and oscillations, without an enzymatic catalyst.

doi: 10.1038/nature19776


An artificial metalloenzyme is compartmentalized and evolved in vivo for olefin metathesis—an archetypal organometallic reaction without equivalent in nature; the evolved metathase reveals broad substrate scope and compares favourably with commercial catalysts.

doi: 10.1038/nature19114


Trace-element analyses of olivine phenocrysts and diamond inclusions indicate that carbonatite-metasomatized subcontinental mantle may be the source of the HIMU mantle end-member, as opposed to recycled basaltic oceanic crust.

doi: 10.1038/nature19113


The authors report on attempts to increase the yield of smallholder farms in China using ten practices recommended by the Science and Technology Backyard for farming maize and wheat at county level.

doi: 10.1038/nature19368


Heterozygous Chd8 mutant mice display autistic-like behaviours and small but global changes in brain gene expression, which are associated with delays in neuronal development.

doi: 10.1038/nature19357


Feedback from the oral cavity to thirst-promoting neurons in the subfornical organ (SFO) during eating and drinking is integrated with information about blood composition, providing a prediction of how oral consumption will affect fluid balance and leading to changes in behaviour.

doi: 10.1038/nature18950


Clock neurons projecting from the suprachiasmatic nucleus activate a thirst-related brain area in mice to cause a surge in drinking just before sleep and thereby to prevent dehydration during the sleep period.

doi: 10.1038/nature19756


The assembly and analysis of complete genomes and large genomic fragments have tripled the number of known ocean viruses and uncovered the potentially important roles they play in nitrogen and sulfur cycling.

doi: 10.1038/nature19366


Yeast central carbon metabolism has been engineered to achieve a more efficient isoprenoid biosynthesis pathway, an advance that brings commodity-scale production of such compounds a step closer.

doi: 10.1038/nature19769


Stem cells generate progenitors that transition through a series of dynamically unstable states with mixed-lineage gene expression, culminating in the specification of cell-fate.

doi: 10.1038/nature19348